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make it a fight between two big eyed groups. Black has the bigger eye and count the inside liberties. His count is: 10 eye liberties, one outside liberty and 2 inside liberties = 13 liberties. White's count is 6 outside liberties and 7 eye liberties = 13 liberties. Black has sente and kills with 3. White has 12 ko-threats.
Allowing mutual life lets White off the hook. However, if you are ahead, even if you know capturing race theory, it may be wise not to give 12 ko-threats to your opponent. On the other hand, if you're ahead, another 45 points may well decide the game.